Catheter ablation is a technique to treat cardiac arrhythmias by creating cell damage. Most forms of catheter ablation for arrhythmias are performed by delivering energy from the endocardial surface of the heart. Only a small proportion of ablation procedures are performed from the epicardial surface of the heart. Surgical ablation of arrhythmias may be performed endocardially and epicardially, but only epicardial ablation may be performed without cardiopulmonary bypass.
While epicardial ablation may be successful in some regions of the heart, in many cases, transmural lesions may be difficult to achieve using an epicardial approach alone. Current approaches to epicardial and endocardial ablation have limitations. One limitation relates to the difficulty with catheter positioning and achieving adequate contact from the endocardial surface that may limit the precision and ease of mapping (obtaining electrical signals from the heart that may identify the site of ablation) and the creation of adequate ablation lesions. Another limitation relates to the tachycardia focus that may require transmural lesions which may be difficult to achieve from either the endocardial or epicardial surface of the heart alone. Yet another limitation relates to some arrhythmias that may require mapping and ablation from both the endocardial and epicardial surfaces and one approach alone is insufficient. Still another limitation relates to the fact that obtaining 2 separate maps of the endocardial and epicardium is time consuming and does not permit one to align the endocardial lesions to create a transmural lesion. The present invention addresses at least one of the limitations and advances the art of endocardial and epicardial ablation by providing a transmural ablation device.